A stalled-ribosome rescue factor Pth3 is required for mitochondrial translation against antibiotics in Saccharomyces cerevisiae

Mitochondrial translation appears to involve two stalled-ribosome rescue factors (srRFs). One srRF is an ICT1 protein from humans that rescues a "non-stop" type of mitochondrial ribosomes (mitoribosomes) stalled on mRNA lacking a stop codon, while the other, C12orf65, reportedly has functions that overlap with those of ICT1; however, its primary role remains unclear. We herein demonstrated that the Saccharomyces cerevisiae homolog of C12orf65, Pth3 (Rso55), preferentially rescued antibiotic-dependent stalled mitoribosomes, which appear to represent a "no-go" type of ribosomes stalled on intact mRNA. On media containing a non-fermentable carbon source, which requires mitochondrial gene expression, respiratory growth was impaired significantly more by the deletion of PTH3 than that of the ICT1 homolog PTH4 in the presence of antibiotics that inhibit mitochondrial translation, such as tetracyclines and macrolides. Additionally, the in organello labeling of mitochondrial translation products and quantification of mRNA levels by quantitative RT-PCR suggested that in the presence of tetracycline, the deletion of PTH3, but not PTH4, reduced the protein expression of all eight mtDNA-encoded genes at the post-transcriptional or translational level. These results indicate that Pth3 can function as a mitochondrial srRF specific for ribosomes stalled by antibiotics and plays a role in antibiotic resistance in fungi.

Minimally invasive hybrid surgery: A salvage tumor enucleation for local recurrence of thoracic esophageal carcinoma after definitive chemoradiotherapy

Local recurrence after definitive chemoradiation for esophageal carcinoma is associated with poor outcomes. Although salvage esophagectomy is a standard treatment that offers a chance of long-term survival, the procedure is associated with high morbidity and mortality. Minimally invasive hybrid surgery (MIHS) employs thoracoscopic and esophagoscopic procedures and is generally used to treat benign esophageal submucosal tumors. A 64-year-old man with thoracic esophageal carcinoma experienced local relapse after definitive chemoradiation. He underwent MIHS and was discharged 18 days after surgery with a slight degree of stricture. Pathological findings revealed squamous cell carcinoma with no residual tumor in the resection margins, and the patient remains free from cancer relapse 24 months after surgery. Here, we report the findings in this patient, in whom MIHS was successfully performed as a salvage tumor enucleation for local recurrence of esophageal carcinoma after definitive chemoradiotherapy.

Simultaneous evaluation of antioxidative serum profiles facilitates the diagnostic screening of autism spectrum disorder in under-6-year-old children

This case–control study aimed to assess oxidative stress alterations in autism spectrum disorder (ASD). We used the MULTIS method, an electron spin resonance-based technique measuring multiple free radical scavenging activities simultaneously, in combination with conventional oxidative stress markers to investigate the ability of this MULTIS approach as a non-behavioural diagnostic tool for children with ASD. Serum samples of 39 children with ASD and 58 age-matched children with typical development were analysed. The ASD group showed decreased hydroxyl radical (^·OH) and singlet oxygen scavenging activity with increased serum coenzyme Q10 oxidation rate, indicating a prooxidative tendency in ASD. By contrast, scavenging activities against superoxide (O₂^·−) and alkoxyl radical (RO^·) were increased in the ASD group suggesting antioxidative shifts. In the subgroup analysis of 6-year-olds or younger, the combination of ^·OH, O₂^·−, and RO^· scavenging activities predicted ASD with high odds ratio (50.4), positive likelihood (12.6), and percentage of correct classification (87.0%). Our results indicate that oxidative stress in children with ASD is not simply elevated but rather shows a compensatory shift. MULTIS measurements may serve as a very powerful non-behavioural tool for the diagnosis of ASD in children.

Does staged surgical training for minimally invasive esophagectomy have an impact on short-term outcomes?

BACKGROUND

sophageal cancer has a low incidence, and the anatomy is difficult to understand during esophagectomy. This necessitates a precise and lengthy operation. Therefore, the establishment of a training system in esophageal surgery is of critical importance. In this study, we compared the short-term outcomes of minimally invasive esophagectomy (MIE) performed by consultants versus trainees and explored the factors that impacted the thoracic operation time for each group.

METHODS

We have introduced standardized MIE surgical techniques to our trainees in 2016. Our procedure consists of a laparoscopic phase and a thoracoscopic phase and is systematically designed to be learned in a step-by-step manner in each phase. We retrospectively identified 308 patients who underwent MIE from April 2016 to April 2018. The patients were divided into those who underwent MIE by consultants and those who underwent MIE by trainees. The preoperative background factors, operation-related factors, and postoperative complications were compared between the two groups. We also assessed the association between a prolonged thoracic operation time and tumor-and patient-related factors in each of the consults and trainees.

RESULTS

Significantly more patients had stage ≥ III cancer in the consultant than trainee group. However, the postoperative complications were comparable, specifically pneumonia (11% vs. 18%), anastomotic leakage (11% vs. 13%), and mortality (0.6% vs. 1.3%). There was no significant difference in the lymph node yield (20 vs. 17) or R0 resection rate (94% vs. 91%) between the two groups. However, the trainees had a significantly longer thoracic operation time (143 ± 34 vs. 190 ± 28 min) and significantly greater blood loss (93 vs. 183 ml). Oncological factors were correlated with a prolonged thoracic operation time in the consultants, but not in the trainees.

CONCLUSIONS

Under standardized surgical management using a stepwise educational program, performance of MIE by trainees has no impact on short-term outcomes.

Efficacy of prewarming prophylaxis method for intraoperative hypothermia during thoracoscopic esophagectomy

BACKGROUND

This study was performed to elucidate the clinical efficacy of the prewarming prophylaxis method for intraoperative hypothermia during thoracoscopic esophagectomy for esophageal cancer.

METHODS

We enrolled 100 consecutive patients with esophageal cancer. Two patients in the prewarming group could not undergo thoracoscopic esophagectomy because of conversion to thoracotomy. The intraoperative core temperature was measured in 50 and 48 patients classified into the control and prewarming groups, respectively. Patients in the prewarming group wore a Bair Hugger warming gown (3 M, Maplewood, MN, USA) in the ward for 30 min before entering the operation room. The primary outcome measure was the difference in the intraoperative body core temperature between the control and prewarming groups, and the secondary outcome measure was the difference in postoperative infectious complications between the control and prewarming groups.

RESULTS

The intraoperative core temperature was significantly different between the two groups at each 30-min time point from the starting of operation to the ending of the thoracic procedure (P < 0.001). The incidence of infectious surgical complications was not significantly different between the control and prewarming groups (30.0% vs. 14.6%, respectively; P = 0.11).

CONCLUSION

The prewarming prophylaxis method was effective for maintaining normothermia during thoracoscopic esophagectomy.

VLDL-specific increases of fatty acids in autism spectrum disorder correlate with social interaction

BACKGROUND

Abnormalities of lipid metabolism contributing to the autism spectrum disorder (ASD) pathogenesis have been suggested, but the mechanisms are not fully understood. We aimed to characterize the lipid metabolism in ASD and to explore a biomarker for clinical evaluation.

METHODS

An age-matched case-control study was designed. Lipidomics was conducted using the plasma samples from 30 children with ASD compared to 30 typical developmental control (TD) children. Large-scale lipoprotein analyses were also conducted using the serum samples from 152 children with ASD compared to 122 TD children. Data comparing ASD to TD subjects were evaluated using univariate (Mann-Whitney test) and multivariate analyses (conditional logistic regression analysis) for main analyses using cofounders (diagnosis, sex, age, height, weight, and BMI), Spearman rank correlation coefficient, and discriminant analyses.

FINDINGS

Forty-eight significant metabolites involved in lipid biosynthesis and metabolism, oxidative stress, and synaptic function were identified in the plasma of ASD children by lipidomics. Among these, increased fatty acids (FAs), such as omega-3 (n-3) and omega-6 (n-6), showed correlations with clinical social interaction score and ASD diagnosis. Specific reductions of very-low-density lipoprotein (VLDL) and apoprotein B (APOB) in serum of ASD children also were found by large-scale lipoprotein analysis. VLDL-specific reduction in ASD was correlated with APOB, indicating VLDL-specific dyslipidaemia associated with APOB in ASD children.

INTERPRETATION

Our results demonstrated that the increases in FAs correlated positively with social interaction are due to VLDL-specific degradation, providing novel insights into the lipid metabolism underlying ASD pathophysiology.

FUNDING

This study was supported mainly by MEXT, Japan.

Molecular determinants of release factor 2 for ArfA-mediated ribosome rescue

Translation termination in bacteria requires that the stop codon be recognized by release factor RF1 or RF2, leading to hydrolysis of the ester bond between the peptide and tRNA on the ribosome. As a consequence, normal termination cannot proceed if the translated mRNA lacks a stop codon. In Escherichia coli, the ribosome rescue factor ArfA releases the nascent polypeptide from the stalled ribosome with the help of RF2 in a stop codon-independent manner. Interestingly, the reaction does not proceed if RF1 is instead provided, even though the structures of RF1 and RF2 are very similar. Here, we identified the regions of RF2 required for the ArfA-dependent ribosome rescue system. Introduction of hydrophobic residues from RF2 found at the interface between RF2 and ArfA into RF1 allowed RF1 to associate with the ArfA-ribosome complex to a certain extent but failed to promote peptidyl-tRNA hydrolysis, whereas WT RF1 did not associate with the complex. We also identified the key residues required for the process after ribosome binding. Our findings provide a basis for understanding how the ArfA-ribosome complex is specifically recognized by RF2 and how RF2 undergoes a conformational change upon binding to the ArfA-ribosome complex.

Case report: Gastric tube cancer after esophagectomy-Retrograde perfusion after proximal resection of right gastroepiploic artery

INTRODUCTION

We report a case of a 57-year-old patient with gastric tube cancer after subtotal esophagectomy and retrosternal gastric pull up.

CASE PRESENTATION

The patient developed gastric cancer 4 years after undergoing treatment for esophageal squamous cell cancer; the treatments included thoracoscopic subtotal esophagectomy, gastric pull-up reconstruction via a retrosternal route in salvage setting following definitive chemoradiation. Because the gastric tube cancer was located around the pylorus, transabdominal partial resection, which is much less invasive than total resection via sternotomy, was performed. During surgery, retrograde pulsation of the proximally resected right gastroepiploic artery was observed. Owing to an ample blood supply to the oral remnant of the gastric tube, vascular reconstruction of the right gastroepiploic artery was omitted. The postoperative recovery was eventless.

DISCUSSION

The right gastroepiploic artery is considered essential for blood supply to the gastric tube. However, there was no sign of ischemia after proximal resection of this artery, which suggests the vasculature was altered after gastric tube construction.

CONCLUSION

This case shows that partial distal resection of the gastric tube can be performed safely without vascular reconstruction of the right gastroepiploic artery. Favorable long-term results after gastric tube reconstruction support the possibility of bilateral blood supply to the gastroepiploic arcade.

Non-occlusive mesenteric ischemia associated with enteral feeding after esophagectomy for esophageal cancer: report of two cases and review of the literature

Background

Non-occlusive mesenteric ischemia (NOMI) is a rare but life-threatening complication of early postoperative enteral feeding. We herein report two patients who developed NOMI during enteral feeding after esophagectomy.

Case presentation

In case 1, a 75-year-old man with no medical history was diagnosed with multiple primary cancers of the esophagus, stomach, and kidney. He underwent percutaneous endoscopic gastrostomy tube placement followed by thoracoscopic esophagectomy and cervical esophagostomy placement as the first-stage operation. Gastrostomy feeding was started on postoperative day (POD) 3 with a polymeric formula (ENSURE H®). On POD 7, he developed acute abdominal pain and distension with bloody drainage through the gastrostomy tube. Dynamic computed tomography showed massive hepatic portal venous gas and pneumatosis intestinalis. Angiography showed diffuse spasms in the branches of the superior mesenteric artery. Under a diagnosis of NOMI, we started intra-arterial infusion of papaverine and prostaglandin E1. His symptoms improved, and he was discharged on POD 48.

In case 2, a 68-year-old man with diabetes and atrial fibrillation was diagnosed with esophageal cancer. His medical history was significant for pylorus-preserving gastrectomy for gastric cancer and small bowel resection for trauma. He underwent thoracoscopic esophagectomy, open total gastrectomy, colonic reconstruction, and jejunostomy tube placement. Adhesiolysis for abdominal severe adhesions caused by previous operations was difficult. Jejunostomy feeding was started on POD 3 with a polymeric formula (Racol®). On POD 7, he developed persistent diarrhea and cervical anastomotic leakage. On POD 9, he developed acute abdominal pain and distension with bloody drainage through the jejunostomy tube. Dynamic computed tomography showed the same findings as in case 1. Under a diagnosis of NOMI, we started intravenous infusion of papaverine and prostaglandin E1. His symptoms improved, and he was discharged on POD 28.

Conclusions

The causes of feeding-related NOMI may include the use of a high-osmolarity formula, preoperative malnutrition, abdominal adhesiolysis, systemic inflammation after anastomotic leakage, and a medical history of diabetes and atrial fibrillation. NOMI should be considered as a differential diagnosis in patients with these risk factors and clinical features such as acute abdominal pain and distension during enteral feeding.

Primary hepatic carcinosarcoma with multimodal treatment

Hepatic carcinosarcoma (HCS) generally presents in advanced stages, demonstrates aggressive behavior, and has a poor prognosis. Other than curative primary resection, no effective treatment options exist. We present a case of resected HCS with four repeat resections for solitary lymph node recurrence followed by chemoradiotherapy with doxorubicin and ifosfamide. A 67-year-old Japanese man was admitted to our hospital for evaluation of an asymptomatic hepatic tumor. The patient underwent right hepatectomy with a presumptive preoperative diagnosis of atypical hepatocellular carcinoma. Based on histopathological and immunohistochemical findings, the tumor was diagnosed as HCS containing osteosarcoma and chondrosarcoma components. After the initial surgery, the patient underwent four additional resections for solitary lymph node HCS recurrence, and then underwent chemoradiotherapy with doxorubicin and ifosfamide for an unresectable lymph node recurrence. Chemotherapy was stopped after two cycles because of severe adverse events, although chemoradiotherapy markedly reduced the size of the lymph node recurrence and provided a progression-free survival of 12 months. Thirty-seven months after the initial surgery, the patient died of cardiac invasion of multiple mediastinal lymph node metastases. The clinical course outlined in this case report suggests that chemoradiotherapy with doxorubicin and ifosfamide for metastatic HCS may prolong survival in patients with unresectable lesions.

Analysis of GNA13 Protein in Follicular Lymphoma and its Association With Poor Prognosis

GNA13 is a G protein involved in modulating tumor proliferative capacity, infiltration, metastasis, and migration. Genomic alteration of GNA13 was frequently observed in follicular lymphoma (FL). In this study, we examined 167 cases of FL by immunostaining of GNA13 using tissue microarray to evaluate the clinical significance. There were 26 GNA13-positive cases (15.6%) and 141 GNA13-negative cases (84.4%). GNA13-positive cases had a higher incidence of early progression of disease for which disease progression was recognized within 2 years compared with GNA13-negative cases (P=0.03). There were no significant differences in other clinicopathologic factors including histological grade, BCL2-IGH translocation, immunohistochemical phenotype, and Follicular Lymphoma International Prognostic Index. In addition, overall survival and progression-free survival were poorer in GNA13-positive cases than in GNA13-negative cases (P=0.009 and 0.005, respectively). In multivariate analysis, GNA13 positivity was found to be a poor prognostic factor for overall survival and progression-free survival. Thus, GNA13 protein expression was an independent prognostic factor and may affect disease progression in FL.

Expression pattern of immunosurveillance-related antigen in adult T cell leukaemia/lymphoma

AIMS

Adult T cell leukaemia/lymphoma (ATLL) is an aggressive malignancy with a poor prognosis. Human leucocyte antigen (HLA) and β2 microglobulin (β2M) serve as key molecules in tumour immunity, and their expression is reduced frequently in tumour cells. Programmed cell death (PD)-1/PD-ligand1 (PD-L1) interactions play a role in escape of tumour cells from T cell immunity. Therefore, this study aimed to determine the clinicopathological relevance of HLA and β2M expressions in ATLL cells and PD-L1 expression in lymphoma or stromal cells and predict the overall survival of patients with ATLL.

METHODS AND RESULTS

We analysed a total of 123 biopsy samples from patients newly diagnosed with ATLL by using immunohistochemical analysis. Of the patients enrolled, 91 (74%) were positive for HLA (in cell membrane, 60 patients), 89 (72%) were positive for β2M (in cell membrane, 54 patients) and 48 (39%) were positive for both HLA and β2M in the cell membrane (HLA^m+ β2M^m+ ). No significant clinical differences other than prognosis were found between the HLA^m+ β2M^m+ group and the other groups. Immunophenotypical evaluation revealed significantly higher rates of CD30-positive lymphoma cells (P = 0.003) and PD-L1-positive stromal cells in microenvironments (miPD-L1^high ) (P = 0.011) of the HLA^m+ β2M^m+ group than in the other groups. The HLA^m+ β2M^m+ group had a significantly better prognosis that the other groups (P = 0.0096), and patients showing HLA^m+ β2M^m+ with miPD-L1^high had the most favourable prognosis among all groups.

CONCLUSIONS

The membranous expression of HLA and β2M is likely to reflect the immune response and would be useful to predict prognosis before starting ATLL therapy.

A distinct subtype of Epstein-Barr virus-positive T/NK-cell lymphoproliferative disorder: adult patients with chronic active Epstein-Barr virus infection-like features

The characteristics of adult patients with chronic active Epstein-Barr virus infection are poorly recognized, hindering early diagnosis and an improved prognosis. We studied 54 patients with adult-onset chronic active Epstein-Barr virus infection diagnosed between 2005 and 2015. Adult onset was defined as an estimated age of onset of 15 years or older. To characterize the clinical features of these adults, we compared them to those of 75 pediatric cases (estimated age of onset <15 years). We compared the prognosis of adult-onset chronic active Epstein-Barr virus infection with that of patients with nasal-type (n=37) and non-nasal-type (n=45) extranodal NK/T-cell lymphoma. The median estimated age of onset of these lymphomas was 39 years (range, 16–86 years). Compared to patients with pediatric-onset disease, those in whom the chronic active Epstein-Barr virus infection developed in adulthood had a significantly decreased incidence of fever (P=0.005), but greater frequency of skin lesions (P<0.001). Moreover, hypersensitivity to mosquito bites and the occurrence of hydroa vacciniforme were less frequent in patients with adult-onset disease (P<0.001 and P=0.0238, respectively). Thrombocytopenia, high Epstein-Barr virus nuclear antigen antibody titer, and the presence of hemophagocytic syndrome were associated with a poor prognosis (P=0.0087, P=0.0236, and P=0.0149, respectively). Allogeneic hematopoietic stem cell transplantation may improve survival (P=0.0289). Compared to pediatric-onset chronic active Epstein-Barr virus infection and extranodal NK/T-cell lymphoma, adult-onset chronic active Epstein-Barr virus infection had a poorer prognosis (P<0.001 and P=0.0484, respectively). Chronic active Epstein-Barr virus infection can develop in a wide age range, with clinical differences between adult-onset and pediatric-onset disease. Adult-onset chronic active Epstein-Barr virus infection is a disease with a poor prognosis. Further research will be needed.

RsgA couples the maturation state of the 30S ribosomal decoding center to activation of its GTPase pocket

During 30S ribosomal subunit biogenesis, assembly factors are believed to prevent accumulation of misfolded intermediate states of low free energy that slowly convert into mature 30S subunits, namely, kinetically trapped particles. Among the assembly factors, the circularly permuted GTPase, RsgA, plays a crucial role in the maturation of the 30S decoding center. Here, directed hydroxyl radical probing and single particle cryo-EM are employed to elucidate RsgA΄s mechanism of action. Our results show that RsgA destabilizes the 30S structure, including late binding r-proteins, providing a structural basis for avoiding kinetically trapped assembly intermediates. Moreover, RsgA exploits its distinct GTPase pocket and specific interactions with the 30S to coordinate GTPase activation with the maturation state of the 30S subunit. This coordination validates the architecture of the decoding center and facilitates the timely release of RsgA to control the progression of 30S biogenesis.

Prognostic factors for histiocytic and dendritic cell neoplasms

Histiocytic and dendritic cell neoplasms are rare and poorly studied. We report the clinical characteristics and prognostic factors in such cases in Japan. We investigated the clinical characteristics and survival in 87 adult patients with histiocytic and dendritic cell neoplasms. Fifty patients had histiocytic sarcoma, 12 had Langerhans cell histiocytosis, 11 had follicular dendritic cell sarcoma, 8 had Langerhans cell sarcoma, 6 had interdigitating cell sarcoma and 1 had indeterminate dendritic cell sarcoma. The median follow-up period was 18.0 (range: 9.6-71.8) months, and median overall survival (OS) was 23.5 months. The 2-year OS rate was 49.2%. In the multivariate analysis, elevated lactate dehydrogenase (LDH) (p =.004), ECOG performance status (PS) 2-4 (p =.006), and Ann Arbor stage III-IV (p =.008) affected OS. Stratification by elevated LDH, ECOG PS 2-4, and Ann Arbor stage III-IV allowed classification of patients into low risk, intermediate risk, and high risk groups. The same classification was applicable for HS and non-HS categories. In the rare neoplasms of histiocytic and dendritic cell sarcoma, ECOG PS, Ann Arbor stage, and LDH are important prognostic factors for predicting survival.

Clinicopathological features of primary splenic follicular lymphoma

Follicular lymphoma (FL) is a low-grade lymphoma that is usually characterized by generalized lymphadenopathy. Extranodal invasion by FL generally involves the bone marrow, skin, and duodenum; splenic infiltration often occurs in the advanced stages. However, primary splenic FL is very rare. Hence, few studies have been performed on splenic FL, and its clinicopathological features have not been established. This study aimed to investigate the clinicopathological features of primary splenic FL, as compared to nodal FL. We analyzed 17 patients diagnosed with primary splenic FL and 153 control patients with systemic FL. Hepatitis C virus (HCV)-positive status was significantly more common in patients with splenic FL than in the control patients (p = 0.02). Ann Arbor stage III or IV (p = 0.0003) and high-risk FLIPI (Follicular Lymphoma International Prognostic Index) (p = 0.03) were significantly less common in patients with splenic FL than in the control patients; however, the overall and progression-free survival curves were not significantly different between the groups. Among the 17 patients with splenic FL, the progression-free survival was significantly worse in patients who underwent splenectomy without receiving postoperative chemotherapy than in those who did (p = 0.03). These results suggest that primary splenic FL should be considered different from systemic FL; accordingly, its management should also be conducted differently.

Comprehensive association analysis of 27 genes from the GABAergic system in Japanese individuals affected with schizophrenia

Involvement of the gamma-aminobutyric acid (GABA)-ergic system in schizophrenia pathogenesis through disrupted neurodevelopment has been highlighted in numerous studies. However, the function of common genetic variants of this system in determining schizophrenia risk is unknown. We therefore tested the association of 375 tagged SNPs in genes derived from the GABAergic system, such as GABA_A receptor subunit genes, and GABA related genes (glutamate decarboxylase genes, GABAergic-marker gene, genes involved in GABA receptor trafficking and scaffolding) in Japanese schizophrenia case-control samples (n=2926; 1415 cases and 1511 controls). We observed nominal association of SNPs in nine GABA_A receptor subunit genes and the GPHN gene with schizophrenia, although none survived correction for study-wide multiple testing. Two SNPs located in the GABRA1 gene, rs4263535 (P_allele=0.002; uncorrected) and rs1157122 (P_allele=0.006; uncorrected) showed top hits, followed by rs723432 (P_allele=0.007; uncorrected) in the GPHN gene. All three were significantly associated with schizophrenia and survived gene-wide multiple testing. Haplotypes containing associated variants in GABRA1 but not GPHN were significantly associated with schizophrenia. To conclude, we provided substantiating genetic evidence for the involvement of the GABAergic system in schizophrenia susceptibility. These results warrant further investigations to replicate the association of GABRA1 and GPHN with schizophrenia and to discern the precise mechanisms of disease pathophysiology.

Clinical effect of immunophenotyping on the prognosis of multiple myeloma patients treated with bortezomib

In the present study, the effect of immunophenotyping on the prognoses of patients with multiple myeloma (MM) treated with bortezomib plus dexamethasone was investigated. The study involved 46 patients with MM, and analyzed the prognostic significance of the expression of cluster of differentiation (CD)45, CD56 and mature plasma cell (MPC)-1, and other factors including the International Staging System (ISS) stage, age, gender, the immunoglobulin subtype and the treatment line number prior to bortezomib treatment. Although CD56 and MPC-1 expression did not appear to affect the time to next treatment (TNT) or overall survival rate (OS), the univariate analysis determined that CD45 positivity was an adverse prognostic factor for TNT and OS, and that being male was significantly associated with inferior TNT and OS. Multivariate analyses determined that CD45 expression was prognostically significant for TNT and OS. In conclusion, CD45 positivity is an adverse prognostic factor in MM patients treated with bortezomib. The data from the present study demonstrate the clinical importance of classifying MM cells immunophenotypically to determine the prognoses of patients.

CCR4 frameshift mutation identifies a distinct group of adult T cell leukaemia/lymphoma with poor prognosis

Adult T cell leukaemia/lymphoma (ATLL) is an intractable T cell neoplasm caused by human T cell leukaemia virus type 1. Next-generation sequencing-based comprehensive mutation studies have revealed recurrent somatic CCR4 mutations in ATLL, although clinicopathological findings associated with CCR4 mutations remain to be delineated. In the current study, 184 cases of peripheral T cell lymphoma, including 113 cases of ATLL, were subjected to CCR4 mutation analysis. This sequence analysis identified mutations in 27% (30/113) of cases of ATLL and 9% (4/44) of cases of peripheral T cell lymphoma not otherwise specified. Identified mutations included nonsense (NS) and frameshift (FS) mutations. No significant differences in clinicopathological findings were observed between ATLL cases stratified by presence of CCR4 mutation. All ATLL cases with CCR4 mutations exhibited cell-surface CCR4 positivity. Semi-quantitative CCR4 protein analysis of immunohistochemical sections revealed higher CCR4 expression in cases with NS mutations of CCR4 than in cases with wild-type (WT) CCR4. Furthermore, among ATLL cases, FS mutation was significantly associated with a poor prognosis, compared with NS mutation and WT CCR4. These results suggest that CCR4 mutation is an important determinant of the clinical course in ATLL cases, and that NS and FS mutations of CCR4 behave differently with respect to ATLL pathophysiology.

Analysis of the BRAFV600E mutation in 19 cases of Langerhans cell histiocytosis in Japan

Langerhans cell histiocytosis (LCH) is a rare disease characterized by clonal proliferation of CD1a- and CD207 (langerin)-positive dendritic cells. Mutated BRAF (p.V600E) is observed in histiocyte-related diseases and dendritic cell-related diseases, including LCH. BRAFV600E is observed in some LCH cases and is thought to be involved in maintaining MAPK activation. We retrospectively analyzed BRAFV600E in 19 patients diagnosed with LCH. In our study, direct sequencing for exon 15, a mutation hotspot, demonstrated that 4 out of the 19 patients (21%) harbored a GTG > GAG (valine > glutamic acid) base substitution, which encodes BRAFV600E. The clinical impact of BRAFV600E in such diseases is unclear. The frequency of BRAFV600E in our LCH patients from Japan was lower than that reported in the United States and in Germany. However, reports from Asia tend to show a lower rate of the BRAFV600E mutation. These results imply the possibility of different genetic backgrounds in the pathogenesis of LCH across various ethnicities. We also performed an immunohistochemical analysis to detect BRAFV600E using the mutation-specific monoclonal antibody. However, immunohistochemical analysis failed to detect any mutated protein in any of the 4 BRAFV600E-positive cases. This implies that at present, BRAFV600E should be assessed by direct sequencing. Copyright © 2016 John Wiley & Sons, Ltd.

Clinical significance of co-expression of MYC and BCL2 protein in aggressive B-cell lymphomas treated with a second line immunochemotherapy

The clinical significance of concurrent expression of MYC and BCL2 protein, known as "double-expressor lymphoma" (DEL), among patients with relapsed or refractory aggressive B-cell lymphomas, remains unclear. A retrospective analysis was performed of 38 patients treated with a salvage treatment consisting of rituximab, ifosfamide, etoposide, cytarabine and dexamethasone followed by consolidative high-dose chemotherapies. A total of 17 cases (45%) were categorized as DEL using immunohistochemical assay with a cut-off value of positivity of 40% for MYC and 50% for BCL2, respectively. DEL was associated with a lower overall response rate (35% vs 71%, p = 0.0481), worse 2-year progression-free survival (9% vs 67%, p = 0.001) and overall survival (35% vs 71%, p = 0.037). This analysis suggests that DEL is common among patients with relapsed/refractory aggressive B-cell lymphomas and that such patients require novel treatment strategies.